1. Field of the Invention
The present invention is generally concerned with the marking of cables or other conductors which may be connected to electrical apparatus, for the purpose of identifying them.
The invention is more particularly directed to the situation in which such marking is carried out by means of at least one marker device which, carrying a marking, more often than not a numeric or alphabetic marking, is adapted to be attached to the cable to be identified, either individually or as part of a group, an appropriately selected plurality of such marker devices being used to compose any required overall marking.
2. Description of the Prior Art
Marker devices of this kind have been known for a considerable time.
The present invention is still more particularly directed to marker devices which comprise two elastically deformable arms integral with a common plate and by means of which they are adapted to form an open loop gripping the cable to be identified.
This applies, for example, to German Pat. Nos. 655 749 and 973 473 and to at least some of the embodiments in Swiss Pat. No. 364 824.
An advantage of these marker devices is that they can be fitted from the side, at any point on the cable to be identified, by means of a simple snap-action engagement on the latter, by virtue of the gap left between the arms and the ability of the latter to deform elastically.
In practice, there is a two-fold problem in producing such marker devices.
The first is concerned with the benefit of being able to fit the same marker device, with well-defined initial dimensional characteristics to cables of different diameters.
The second is concerned with the benefit to be obtained by ensuring that, once fitted to a cable, the marker devices attached to the latter are prevented from rotating on it to a sufficient extent so as to always remain appropriately oriented in the direction enabling the marking on them to be read, whilst also being capable of being rotated on the cable to adjust their position on the latter.
In the aforementioned German Pat. No. 655 749 it is proposed to provide each arm with a finger directed inwardly and towards the plate and through which the arm is adapted to bear on the cable to be identified.
Although a marker device of this type can adapt to cables of different diameters, by virtue of the additional capacity for elastic deformation due to the fingers thus associated with its arms, its transverse retention on a cable is in practice inadequate.
The reason for this is that such retention is due essentially only to the fingers on the arms, without the participation of the plate which is common to the latter.
Taken overall, a marker device of this kind can thus give elastically relative to the cable it is gripping, in particular in line with its plate, which is not aligned with any well-defined reference position.
In German Pat. No. 973 473, and this applies also to Swiss Pat. No. 364 824, the plate common to the two arms of the marker device in question participates in retaining the latter on a cable.
However, the arms intervene directly and thus with a necessarily limited capacity for elastic deformation, and therefore marker devices of this kind are in reality adapted only to cables on a particular diameter.
A general object of the present invention is a cable marker device offering the advantageous combination of an extended capacity for adapting to cables of different diameters with proper retention on such cables.